Frigid weather makes some aspects of pipeline construction more difficult, though not impossible, engineers and experts interviewed by Reuters said this week. That stretch would be expected to take 90 to 120 days to finish, ETP has said. The median temperature in Morton County, North Dakota, near the pipeline route is 13 degrees F between December and February, according to the National Weather Service. Hansen added that the high winds in North Dakota and heavy snow accumulation can also slow operations.